It looks you used the build-in flash of your camera.
Since you don't have an external flash you could "enhance"the "quality" of the final image simply by placing a black sheet/paper behind the flower so you have at "least" a "homogeneous" background that makes your flower "pop-up".
Your photo has very nice colors (even if a "direct/harsh"light source was used) but the background is a little bit messy!!!

Thanks for the great advice karaflazz; if this had been a setup shot I may have done just that; however this was a point and shoot on the run snapshot, unplanned and unrehearsed. Cropped a bit to fit theme since it seemed to fit it so well